1. Field of the Invention
The present invention relates to an index print producing method, an image processing system, an image processing device and an image processing method. More particularly, the present invention relates to a method of producing an index print in which a plurality of images are disposed in a predetermined layout; an image processing system in which the index print producing method can be used; an image processing method and an image processing device which are capable of correcting aberrations when an image recorded on a photosensitive material is image processed; an image processing device having functions of image processing image data such that the outer peripheral shape of an image represented by the image data is changed and extracting data corresponding to an instructed range from the image data; an image processing method for correcting at least one of a geometrical distortion or a color misregistration of an image of image data representing an image projected through a lens; and an image processing device to which the image processing method can be applied.
2. Description of the Related Art
Conventionally, a photographic film having a plurality of images recorded thereon has been developed by exposure-recording the plurality of images onto photographic paper in such a way that the images are arranged in a matrix configuration on a single sheet, thereby creating what is known as an index print (refer to Japanese Patent Application Laid-Open (JP-A) No. 9-90528 and the like). By referring to the index print, a user is able, with one glance, to confirm the images recorded on the photographic film. Therefore, the user is able to easily specify images which the user wishes to be reprinted and to organize the photographic films.
On the other hand, an image processing system is known which subjects, to a variety of image processings, image data obtained by reading film images recorded on a photographic film or image data input from a digital camera or the like. After the various image processings have been completed, the images are recorded on a recording material, such as photographic paper, displayed on a display means, such as a display unit, or the image data is stored on an information recording medium. Thus, the image processing system is able to output the image (a main image) in a variety of forms. As compared with the conventional photograph processing system for recording a film image on photographic paper by a single exposure of the surface of the photographic paper, the above-described image processing system is able to arbitrarily control the quality of a recorded image by processing image data of the image. Therefore, the quality of a main image (an image recorded on a recording material, an image displayed on a display means or an image indicated by image data stored in an information recording medium) can be improved.
The above image processing system is able to employ a plurality of standard image processings for improving the quality of the main image. The standard image processings include gradation conversion, color conversion, a hyper-tone processing for compressing the gradation of extremely low frequency luminance components in an image and a hyper-sharpness processing for emphasizing sharpness while suppressing graininess are selectively performed on each image unit (or a film unit) Non-standard image processings include: an image processing for improving the quality of a main image when an image recorded by photography using a film with an attached lens is used as the original image (for example, processings to correct distortions in the original image caused by distortion aberrations in the lens and processings to correct color misregistration with the original image caused by color aberrations from the lens magnification); an image processing to intentionally change the image tone (for example, image processings to give a monotone completed image from a main image, a portrait tone completed image from a main image, and a sepia tone completed image from a main image); and an image processing to process an image (for example, an image processing to slenderize in the main image a person appearing in the original image) These non-standard image processings are selected to be automatically executed or selectively executed in accordance with an instruction issued from a user.
The above-described image processing system is structured so that the data of an original image is temporarily stored in a memory, the data of the original image is then read from the memory, and the read data of the original image is then subjected to an image processing in accordance with the contents (whether or not each type of image data processing is executed and the processing conditions of executed image data processings) of the processing previously determined on the basis of the results of analysis of the contents of the image. Thus, image data of the main image is output as data. Therefore, when an index print is produced, the data of a plurality of original images to be recorded as the index print are disposed in the memory in accordance with a predetermined layout. Thus, image data for producing the index print is produced. Then, the image data is read from the memory and subjected to image processing having a fixed content. Image data subjected to the image processing is used to expose and record the index print image on a recording material. Thus, the index print can be produced.
As described above, the aforementioned image processing system produces an index print by subjecting the data of a plurality of original images to image processing having a fixed content. Therefore, images which are recorded as the index print usually contain a multiplicity of images in finished states considerably different from the finished state of the main image (for example, images subjected to additional non-standard image processing when the main image is output). The reason for this lies in the fact that image processing is performed having a content which is considerably different from the content of the image processings which are performed to output the main image.
When output is performed such that, for example, a main image is recorded on a recording material or a main image is displayed on a display means, referring to each image on the index print does not always enable the finished state of the main image corresponding to each image to be recognized. Therefore, it is not always possible to ascertain which of the plurality of main images output from the image processing system corresponds to a particular image on the index print. When output is performed by storing the image data on an information recording medium, the main image represented by the image data stored on the information recording medium cannot visually be recognized. Therefore, the service of producing and making available the index print is an advantageous service which enables the main image to be confirmed. However, since the finished state of each image on the index print is sometimes considerably different from the finished state of the main image, there is a fear that the finished state of the main image represented by the image data stored on the information recording medium will be incorrectly recognized.
A conventional image processing device is known which obtains digital image data of a film image by using a sensor, such as a CCD, to read the film image recorded on a photographic film and then prints and exposes the image on photographic paper in accordance with the obtained digital image data.
In recent years, this type of image processing device has enabled stable print quality by subjecting obtained image data to a variety of correction processings. For example, chromatic aberration of magnification (the position of a pixel is different for each R, G, B color) and distortion aberration (the image is distorted) which easily occur when a low-cost camera, such as a film with an attached lens or a compact camera, is used to take a photograph can be corrected.
However, when the above-mentioned aberration correction is performed, the following problem arises: when, for example, distortion aberration correction is performed, an image such as that shown in FIG. 11A becomes what is known as a pincushion distorted image as shown in FIG. 11B. In this case, regions having no image indicated by the diagonal lines in the figure, that is, what are known as image voids occur. Therefore, a satisfactory printed image cannot be obtained. Because of this, the rectangular region 306 (marked by the dotted lines in FIGS. 11B and 11C) containing no image void regions is enlarged to the desired print size so that a printed image with no image voids is obtained. However, if the face of a person is positioned at an edge of the image as shown in FIG. 11B, a portion of the face is, cut out on the printed image even though the face was photographed in its entirety.
A conventional image processing system is known in which image data obtained by reading a film image recorded on a photographic film or image data input from a digital camera is subjected to a variety of image processings. The image is then recorded on a recording material, such as photographic paper, or the image data is stored on an information recording medium. Thus, output of the image can be performed in a variety of forms. As compared with the conventional photograph processing system for recording a film image on photographic paper by a single exposure of the surface of the photographic paper, the above image processing system is able to freely control the image quality of the output image by performing image processing on the image data, allowing the quality of the output image can be improved.
If image output is again requested, the above image processing system is able to perform a processing known as cropping in which image data in an arbitrary range (a range instructed by the user)is extracted; an image in the instructed range is enlarged and recorded (the cropping range) using image data subjected to an enlarging by electronic power variation; and image data is stored in an information recording medium. Note that when the cropping processing is carried out, the original image which is to be cropped is displayed on a display unit and the cropping range is instructed by the user who indicates on the surface of a display unit the positions of the edge of the range to be cropped, thus allowing the cropping range to be recognized on the basis of the indicated edge positions.
Since a film with an attached lens usually incorporates a low-cost plastic lens, aberration, such as distortion aberration and chromatic aberration of magnification, is great. A film image exposed and recorded on a photographic film using a film with an attached lens undergoes relatively considerable geometrical distortion aberration (called “pincushion distortion aberration”) as shown in FIG. 16A (note that FIGS. 16A and 16B show an example in which an image having a multiplicity of lines disposed in a lattice configuration has been photographed and recorded on a photographic film using a film with attached lens). Moreover, relatively considerable color misregistration caused by chromatic aberration of magnification of the lens takes place. Therefore, an attempt has been considered to obtain an output image having excellent quality from the image of the above type by performing distortion aberration correction to correct geometrical distortion aberration of an image caused by distortion aberration of the lens. Moreover, an attempt has been considered to correct chromatic aberration of magnification such that color misregistration of an image caused by chromatic aberration of magnification of the lens is corrected.
For example, distortion aberration correction is performed by measuring and storing in advance data for each type of lens for correcting distortion aberration indicating the direction and distance moved by the position of each pixel caused by the distortion aberration of the lens with respect to an original reference position (a lattice point) of each pixel constituting a film image. Then, data for correcting the distortion aberration for the type of lens used in the photographing operation is fetched for the image data to be processed. On the basis of the fetched data for correcting the distortion aberration, the position of each pixel represented by the data of each pixel when no distortion aberration occurs is determined. Thus, the density value at the original position (the lattice position) is obtained by performing interpolation calculation.
However, since the image data is data having a large data quantity and representing an image spreading two-dimensionally, the contents of the processings to correct aberration, such as distortion aberration correction and correction of chromatic aberration of magnification are complicated. Therefore, a long time is required to complete the processing and a storage means having a large capacity must be provided. As a result, there arises a problem in that the structure of an image processing section for performing the processing for correcting aberration becomes too complicated. What is worse, the processing performance of the image processing system deteriorates.
For example, distortion aberration correction is performed by measuring and storing in advance data for each type of lens for correcting distortion aberration indicating the direction and distance moved by the position of each pixel caused by the distortion aberration of the lens with respect to an original reference position (a lattice point) of each pixel constituting a film image. Then, data for correcting the distortion aberration for the type of lens used in the photographing operation is fetched for the image data to be processed. On the basis of the fetched data for correcting the distortion aberration, the position of each pixel represented by the data of each pixel when no distortion aberration occurs is determined. Thus, the density value at the original position (the lattice position) is obtained by performing interpolation calculation. Among the above processings, the interpolation calculation of the density value at a lattice point position requires that the density values at the lattice point position be estimated for each of the two-dimensionally distributed plurality of lattice points from the density values of the plurality of pixels existing around the lattice point (the pixels in a region two-dimensionally spreading from the lattice point). Therefore, the processing is extremely complicated.
Because the distortion aberration correction is correction which goes together with the movement of the positions of pixels represented by pre-corrected image data, the shape of the image represented by the corrected image data is also changed from a rectangular shape to a non-rectangular shape (for example, to a barrel shape or a pincushion shape) by the aberration correction. If an image in a pincushion shape and having geometrical distortion aberration as shown in FIG. 16A due to distortion aberration is subjected to distortion aberration correction, the shape of the image represented by the corrected image data is formed into a barrel shape as shown in FIG. 16B. Since the outline of an image usually has a rectangular shape, the cropping range is formed into a rectangular shape to match the shape of the image. Therefore, when an instruction is given to execute cropping of an image which is to undergo distortion aberration correction with the image, represented by image data not having undergone distortion compensation correction, displayed on a display unit, then, on the basis of the displayed image, if a range including areas outside the outline of an image represented by corrected image data is indicated as the range to be cropped, blank areas and areas where the density values are uncertain occur in portions of the cropped image (the blank areas, known as image voids, shown in the four corners of the image in FIG. 16B). Moreover, since the correction of chromatic aberration of magnification is also a correction accompanying a movement of the positions of pixels, in spite of the distance moved being very small, a equivalent problem arises.
To prevent the above problem, specification of the range to be cropped is required to be performed as follows: a user recognizes whether or not the specified image is an image to be subjected to aberration correction. If the specified image is an image to be subjected to the aberration correction, the user must determine the range in the original image which is able to be cropped. Therefore, a complicated operation for specifying the range to be cropped is required. In addition, the user cannot specify an appropriate range to be cropped, and as a result, there is the concern that blank areas or images having uncertain density values will be formed in portions of the cropped image.